In this paper, we describe new methodologies for reinforcing the social consensus building of the multicultural coexistence assistance using participatory simulation in civil societies. In this methodology, both human and intelligent software agents participate in a participatory gaming simulation. They have mutual interactions on the computer network, and accumulate decision-making steps. This simulation, which has mutual interaction between humans and agents, can achieve the gathering and analyzing of beneficial information to solve problems in multicultural civil societies. This type of simulation will help to provide knowledge for the formulation of social consensus, and to create new opportunities for discussion with people with different cultures and social backgrounds.